Electromechanical Transmission Research Articles

Motor fault diagnosis based on composite multi-scale weighted reverse slope entropy and neighborhood preserving embedding

The motors are critical components of the electromechanical transmission in vehicles, and its operating status directly affects the maneuverability of vehicles. To quickly and accurately identify the operating status of motors, this paper proposes a new entropy - Composite Multi-scale Weighted Reverse Slope Entropy (CMWRSlE) for motor fault diagnosis, which is a more interpretable entropy due to its deep exploration of signals. Firstly, the composite multi-scale weighted reverse slope entropy values are extracted from the vibration signals of the motor in different states; Secondly, the extracted features are dimensionally reduced by the manifold learning algorithm – Neighbourhood Preserving Embedding (NPE) and classified by the hierarchical prototype-based approach (HPA) to achieve the fault diagnosis of the motor. Finally, the method proposed in this paper is validated through two sets of experimental data: motor rotor faults and motor bearing faults. The results show that the accuracy of the proposed method in motor fault diagnosis reaches 100 %, which indicates the effectiveness of the proposed method.

Study results in curvilinear motion of high-speed track machine with electromechanical transmission

Introduction. Transport and technological means based on tracked undercarriages have found their use in both military and civilian industries. Their widespread use is due to a number of advantages that contribute to the further development of mechanization of production, increasing the efficiency of transportation of minerals, and developing infrastructure during the development of new territories. Ensuring cross-country ability and mobility of vehicles with tracked undercarriages, including tracked conveyor-tractors, is possible through the use of hybrid electromechanical transmissions. One of the components of scientific research in this direction is carrying out simulation modeling of the movement of equipment. Modeling the motion process will make it possible to substantiate the energy characteristics of the electromechanical transmission of a tracked vehicle and confirm the adequacy of previously performed theoretical studies.Research methods. The main objective of the simulation was to confirm the effectiveness of the theoretical studies performed. The studies in the VISSIM programming environment using typical motion cycles that equivalently reflect the operating conditions and use of a tracked machine were carried out.Results. As a result of the research, quantitative estimates of the influence of the power of a diesel generator and the charge of an energy storage device on the dynamic performance of equipment were obtained. It has been established that in order to meet the requirements for promising samples, the power of the energy storage device should be at least 2.5 kWh when using a standard internal combustion engine.Discussion and conclusion. The research results can be used to create, based on the existing scientific and technical background, a promising robotic complex with an electromechanical transmission.

ENERGY EFFICIENCY OF A HYBRID ROAD TRAIN WITH AN ACTIVE SEMI-TRAILER FOR ROAD CONSTRUCTION WORK

The previous experience of creating experimental road trains with an active trailer and semi-trailer is analyzed against the background of modern technological capabilities of transport engineering and the logistical needs of modern construction. The expediency of implementing the concept of a road train with an active trailer based on modern electromechanical technologies is shown. The purpose of the study is to increase the energy efficiency of road trains used in construction for transporting long-length objects (beams, piles, bridge trusses, panels, etc.) by using an active trailer link with an electromechanical drive. The study solves the problem of modeling the movement of road trains with passive and active semi-trailers and comparing their energy efficiency and safety indicators. The methods of modeling the movement of cars and road trains, characteristic of the theory of movement of transport vehicles, approaches of theoretical mechanics and applications of differential calculus, applied numerical modeling in the SimuLink environment are used. A mathematical model has been obtained that allows calculating the energy efficiency of a road train when using passive (towed) and active semi-trailers. The cycle of the road train movement has been developed and tested for use in severe road conditions (construction with weak road infrastructure, forest complex, transportation of special cargo). The implementation of the computational model by means of the SimuLink software package is proposed. Based on the simulation results, conclusions are made on the energy efficiency and safety of road trains with an active trailer link with an electromechanical transmission.

Energy balance of a wheeled vehicle with an electromechanical transmission

For modern urban infrastructure, the use of trackless electric vehicles for transporting goods and passengers is relevant. The environmental aspect also plays an important role - the absence of exhaust gas emissions and the redistribution of environmental load between the regions of operation and production and disposal of vehicles and electrical energy. However, in many cases, laying wire lines is difficult, and in large cities, due to large traffic flows, the maneuverability of machines connected to the overhead wire is significantly limited. To ensure the energy autonomy of a transport vehicle for at least a working day, the installation of heavy and expensive batteries that take up large volumes is required. The purpose of the study is to reduce the capacity requirement of the on-board power supply by using the principle of palliative charging. The article discusses the concepts that provide such an approach. The main task is to build an energy balance for a vehicle with an electromechanical transmission used for passenger transportation in an urban environment. The assumptions necessary for constructing the methodology are given. When compiling the driving cycle, the requirements of the standard for organizing transportation by electric vehicles are used.

Power distribution mechanisms with friction control in the transmission of a road train with an active trailer-dissolution

The article analyzes the experience of using gear controlled power distribution mechanisms in transport engineering as part of a dynamic stabilization system for high-speed ground vehicles. An overview of the sources on this issue is given. It is shown that the issue of increasing the lateral stability against skidding is relevant in modern conditions and has received a mathematical description mainly in the application to passenger cars. Attention is paid to theoretical studies of Russian scientists involved in the problem of power distribution control in transmissions of transport vehicles and tractors for various purposes. A solution to the problem of full control over the distribution of torques in a transmission containing several drive axles is proposed in the form of a structural diagram of a transmission based on the use of controlled gear power distribution mechanisms. The considered solutions are applicable for monohull vehicles and road trains with an active trailer link. Methods for determining external parameters (gamma of gear ratios) for interaxle and interwheel controlled power distribution mechanisms are proposed in the application to the case of turning a road train with an active trailer-dissolution having an electromechanical transmission.

Алгоритмы управления карьерным самосвалом при проскальзывании колес

Mine dump trucks with a carrying capacity of 90 tons or more are equipped with an electromechanical transmission that controls the traction motors of the driving wheels. Due to unfavorable operation conditions of dump trucks, there are strict requirements to the driving safety along unpaved roads of open pits. The results of BELAZ dump trucks tests and authors maintenance experience have shown that the active security system is especially needed and gives essential assistance to a driver. Loss of control of а loaded truck, for example, during sharp braking on a slippery icy road, can lead to а serious accident and additional costs for repairing mining equipment. Thus, the development of traffic safety systems of mine dump trucks with electromechanical transmission is an important task. The methods of automatic control, mathematical modeling and numerical solution of differential equations are used to develop control algorithms for a mine dump truck. To test the proposed solutions, the method of full-scale experiment is used in real-life driving conditions along the dirt and icy roads. Control algorithms that use data of additional front (driven) wheels sensor are proposed. The results of tests of a BELAZ dump truck with a carrying capacity of 90 tons are presented. The results confirm the effectiveness of the developed control system in comparison with the one currently used in stock-produced items. The developed ABS system with speed sensors of the front wheels of a dump truck has proved the braking effectiveness along a slippery road. It makes it possible to improve the controllability of the dump truck significantly under conditions of lack of road adhesion, preventing the dump truck from skidding and wheels blocking. And it makes it possible to reduce mechanical effects on the transmission and anti-slip system sensitivity to different traffic conditions. The adaptive system remains operational if one of the front wheel sensors fails and if compared to the standard system it works equally effectively in various traffic conditions. The implementation of the obtained results will improve traffic safety and reduce the accident rate of expensive mining equipment.

Non-invasive Evaluation of Electromechanical Transmission in Patients with Hypertensive Response to Exercise Stress Test.

Excessive hypertensive response to exercise testing is associated with adverse cardiovascular events such as left ventricular hypertrophy and atrial fibrillation (AF). In this study, we examined the relationship between electromechanical delay and excessive hypertensive response to exercise testing. Twenty-five people who had a hypertensive response to the exercise stress test and 28 people who were similar in age and gender with a normal blood pressure response in the exercise stress test as the control group were included in the study. There was no statistical difference between the study groups in blood pressure holter values, conventional echocardiography findings, and exercise stress test findings. Lateral PA-TDI time (the time from the beginning of the P wave measured by tissue Doppler imaging to the beginning of the A' wave), left atrial electromechanical delay, and interatrial electromechanical delay were observed to be significantly longer in the hypertensive response group to exercise stress test compared with the control group (74.0±6.3 vs. 68.8±5.7, p=0.003; 24.7±7.0 vs. 19.6±7.1, p=0.013; 36.8±8.5 vs. 30.6±6.6, p=0.003, respectively). Early detection of electromechanical delay non-invasively may be useful in this patient group in predicting the development of new AF risk.

Удаленная работа с комплектом тягового электрооборудования карьерного самосвала

The electromechanical transmission of a mine dump truck is an electrical equipment complex with a set of parameters for setting and status monitoring. To improve the quality and to reduce the time and cost of service maintenance of mine dump trucks, a data transmission system is organized that provides remote work with control system units. Such systems significantly increase the efficiency of operation of mine dump trucks with the integrated use of a standard approach to maintenance and repair of mining equipment and mobile technologies. They allow to identify most of the faults due to the use of a real-time parameter monitoring system during the routine operation of mine truck. The authors have used the methods of design and software architecture, methods of object-oriented programming and development of multi-threaded applications using the high-level programming language C/C++. The paper proposes a functional diagram of data transmission for remote operation with electrical equipment blocks. The description of the instrumental software for monitoring and configuring the parameters of the dump trucks electric transmission is given. A procedure for remote work with a set of traction electrical equipment has been developed. The developed system has been tested at the stages of testing and adjustment. It is used in real operating conditions and allows organizing service maintenance of domestic-made dump trucks at a level that is not inferior to their best imported counterparts. The use of an integrated approach and the extended list of diagnostic parameters of the electric transmission when it is singled out as a separate element of the diagnostic system significantly improves the quality-of-service maintenance of traction electrical equipment.

Electromechanical transmission for active release trailer

The issues of the features of the use of active trailers as part of road trains of forest machines are considered. The principles of constructing a block diagram, determining external parameters and synthesizing kinematic diagrams of the mechanical part of the electromechanical transmission of an active trailer are proposed. A variant of the kinematic scheme of the power distribution mechanism is given. A technology for controlling such mechanisms is proposed. The ways of project realization are shown.

The analysis of principles of continuously variable transmission of tractors

BACKGROUND:Modern agricultural activity requires the use of hightech equipment such as, in particular, a multifunctional tractor, which, according to actual trends, should be an autonomously controlled mobile power plant. In modern tractors, meeting current requirements, multiflow shaft-planetary gearboxes with cumulative effect are used.
 AIMS:Comparison of the operation principles of two types of automatic tractor transmissions: with hydrostatic drive and with electromechanical drive.
 METHODS:During the research, a literature review of printed and online publications with technical description of the transmissions of the considered design was carried out.
 RESULTS:The operation principles of two types of automatic tractor transmissions were considered: with hydrostatic drive (Fendt VarioDrive) and with electromechanical drive (Ruselprom-electroprivod LLC).
 The operation principle of the Fendt VarioDrive transmission (planetary multiflow transmission with mechanical and hydrostatic branches) consists in dividing the torque coming from the internal combustion engine by a planetary gearbox into mechanical and hydrostatic branches, followed by summation of flows by a collecting shaft. The change in the gear ratio and movement direction of the tractor is controlled by the ECU by means of controlling the hydrostatic branch of the transmission. The transmission is nominally continuously variable due to the absence of gears as such.
 The set of traction electrical equipment of the transmission developed by Ruselprom- electroprivod LLC, installed on a tractor, includes:
 an synchronous motor generator with a power converter and a microprocessor control system;
 a traction asynchronous motor of the central drive with a power converter and a microprocessor control system;
 a DC-DC converter for energy supply of auxiliary equipment.
 power converters and a DC-DC converter are integrated into the power electronics unit;
 a top-level controller with controls and indicator panel in the drivers cab.
 The control system of the electromechanical transmission provides with full control of its operation and the functioning of the internal combustion engine. The operation principle of the system is based on the essentials of hybrid transport operation. Tractor movement is possible in one of two ranges: range 1, operational (0...18 km/h) and range 2, transport (0...42 km/h)
 CONCLUSIONS:Due to the modern concept of electric drive units, layout solutions with an electromechanical drive having an electric generator in their design are more promising and applicable in the future, especially for trailed equipment.

Research on fault diagnosis method of electromechanical transmission system based on one-dimensional convolutional neural network with variable learning rate

As an important part of many mechanical equipment, the mechanical transmission system is very important to carry out efficient and accurate fault monitoring and diagnosis. Compared with traditional fault diagnosis techniques, such as spectrum analysis, deep learning has been widely used in the field of mechanical system fault diagnosis due to its powerful data expression ability, and has achieved certain research results. One-dimensional convolutional neural network is a widely used model for deep learning, so in this paper, the one-dimensional convolutional neural network (1D-CNN) in the deep learning theory and the vibration signal analysis method are integrated and applied to the fault identification of mechanical transmission system to achieve accurate diagnosis and classification of faults. The experiment is mainly to collect the vibration signal data of different fault states such as broken teeth, cracking, shaft unbalance, bearing wear, and excessive friction of the driven wheel of the mechanical transmission system, it was divided into training set and testing set according to an appropriate proportion, and 1D-CNN was built using Python. The deep learning model deeply analyzed the influence of different data sample sizes and different model parameters on the recognition accuracy, and obtained an ideal diagnostic model based on variable learning rate through parameter adjustment and comparative analysis. This experimental results show that the recognition method based on one-dimensional convolutional neural network can be effectively applied to the fault diagnosis of related mechanical transmission, and has a high diagnosis accuracy.

Fixed-time Prescribed Performance Vibration Suppression Control of the Electromechanical Transmission System with Actuator Faults

Fixed-time Prescribed Performance Vibration Suppression Control of the Electromechanical Transmission System with Actuator Faults

Discovering New Prognostic Features for the Harmonic Reducer in Remaining Useful Life Prediction

Vibration and current signals are widely used in fault diagnosis and life prediction of electromechanical transmission systems. However, due to the complex working environment of harmonic reducer in the industrial robot, using a single signal for failure analysis or life prediction may risk to false alarming due to lacking of fault information. In the early operation stage of equipment, fault information contained in the signal is too weak to be extracted. In addition, there is certain correlation among the features, which can lead to meaningless superposition of the calculation process. Therefore, a new health index construction method is proposed integrating the current signal and vibration signal and reducing the redundancy among the features in multidomains and can effectively enhance the fault information. In addition, in view of the local optimum and slow speed caused by the random initialization of the network model, an improved life prediction method is proposed to optimize BP neural network to improve the prediction performance. The proposed method is verified by the test data of the harmonic reducer. Results show that the proposed method can predict the remaining useful life of the harmonic reducer more accurately and effectively.

The double-flow electromechanical transmission of tracked vehicle

BACKGROUND: Specific demands to ensure high mobility and low energy consumption while cornering are given in the process of development transport and special tracked vehicles. Therefore, improvement of values of these parameters is a relevant objective. The mentioned parameters are directly dependent on the chosen type of transmission.
 AIM: Derivation of transmission kinematic schemes that provide the best opportunities to ensure the quality of tracked vehicle cornering control with relative simplicity of design.
 METHODS: Derivation of transmission kinematic schemes and analytical evaluation of expected transmission properties were based on fundamentals of the theory of ground vehicle dynamics.
 RESULTS: The kinematic diagram of a double-flow transmission and rotation mechanism for a transport vehicle with two engines is proposed. The proposed scheme is applicable for tracked chassis, wheeled vehicles using the skid-steering method. The proposed principle of transmission construction can be adapted for a ship with a hybrid powerplant. The modes of operation of the proposed mechanism are presented, its main kinematic and power features are given. An assessment of the required power of the traction electric motor as part of a hybrid powertrain of a transport tracked vehicle weighing 4550 tons was carried out. Special attention is paid to the problem of the possibility of manufacturing a hybrid powertrain with the proposed transmission based on components, the production of which has been produced in the Russian Federation.
 CONCLUSIONS: The proposed transmission scheme may be used for development of new machinery as well as for upgrading of existing vehicles. Main advantages of the proposed scheme are simplicity, compactness, and engine functions duplications. Specific advantages for a transport vehicle with an regenerative steering system are ensuring the mechanical energy recuperation during cornering and braking and ensuring turning the production of a pivot turn.

The study of motion of the snow and swamp-going vehicle with the traction electric drive, based on the Emrax 228 electric motor

BACKGROUND: Ensuring transport accessibility of arctic zones of the RF, according to the strategy of social and economic development of the Russian Federation until 2030, is an important and relevant objective.
 AIMS: The article contains the results of the study of motion of the 6WD snow and swamp-going vehicle with traction electric drive, developed at the Wheeled vehicles department of Bauman MSTU as part of development of snow-going vehicles line-up for the sake of improvement of transport accessibility for people living in arctic zone of the RF.
 METHODS: On the basis of the RM 650-2 6X4 all-terrain vehicle, the state-of-the-art electric snow- and swamp-going vehicle with a light-weight welded frame, an electric power unit, a lithium battery as a power-supply source and electromechanical transmission was designed. The vehicle equipped with systems of control, cooling and lighting as well as sensors and measuring complexes. Studies were carried out with various vehicle operation modes (on direct gear with current limit, without current limit and on low gear). Soil road and prepared cross-country terrain were used as a profiled track.
 RESULTS: The time-domain diagrams of traction electric drive operation and the vehicle dynamic characteristics were obtained as the study results.
 CONCLUSIONS: The obtained values and characteristics point at high level of vehicle power equipment and at prospects of designs, used in the snow-and swamp-going vehicle. The study results can be used for modernization of existing vehicles and for development of high-technology machinery, based on electric power unit.

Evaluation of Electromechanical Transmission System at Vehicle Level

With the rapid development and maturity of new energy technologies, electromechanical transmission systems, which deeply integrate electric transmission and mechanical transmission technologies, have been widely used in various vehicles and equipment. To ensure high efficiency and reliability of electromechanical transmission systems, this study investigated the vehicle-level comprehensive performance evaluation index system for an electromechanical transmission while focusing on the electrical properties of the transmission system. An evaluation index was constructed for the vehicle-level electromechanical transmission system. An expert investigation method was used to select and optimize the evaluation indicators, and the evaluation index system for the electromechanical transmission system was obtained. Based on an analytic hierarchy process and the grey relational algorithm, a vehicle-level evaluation method was established for the electromechanical transmission system. This study provides a theoretical basis and guidance for the validation, development, and design finalization of electromechanical hybrid vehicles.

Method for applying vehicle driving cycles to assess the durability of electromechanical transmissions of trucks

The article discusses the relevance of the problem of calculating the elements of electromechanical transmissions of trucks for strength and durability. The main methods used for the formation of load conditions on electromechanical transmissions of trucks are given. The driving cycles of trucks used to obtain loads when calculating the durability of the elements of electromechanical transmissions are given. The universal driving cycles of vehicles obtained on the basis of the collection of statistical data on the movement of trucks are considered. A simulation model of the movement of a truck used to determine the loads on the electromechanical transmission while overcoming driving cycles of trucks is presented. The durability of the gears of the electromechanical transmission of a truck is analyzed on the basis of load cyclograms obtained during simulation modeling of movement. Numerical results of the safety factors of one of the gear stages are obtained. Conclusions are drawn about the optimality of the use of existing driving cycles of trucks in strength calculations. Conclusions are worded about the need to synthesize driving cycles of trucks based on the collection of statistical data on the movement of truck vehicles on the territory of the region under consideration.

Fire extinguishing systems for dump trucks

The paper presents a classification of fire extinguishing systems for dump trucks. The principles of fire-extinguishing systems operation are given according to the method of actuation and purpose of applied extinguishing agents. Manufacturers of fire-extinguishing systems for mine dump trucks are marked, and technical characteristics of their systems are represented. As a result of the research, it has been determined that the main direction of development of fire-extinguishing systems is connected with extinguishing of class E fires, because of increase in demand on CW with electromechanical transmission, the most perspective systems of fire-extinguishing are systems with automatic switching, with possibility of manual switching.

Determination of the number of speeds of a mechatronic transmission of a road car based on a typical specified driving mode

The article discusses the problem of determining the rational number of gears for a mechatronic transmission of a truck vehicle. A review of the designs of existing mechatronic transmissions from leading manufacturers of motor vehicles was carried out, with an emphasis on analyzing the number of gears used in them. A method has been developed for determining the rational number of gears based on simulation modeling of the movement of a truck along driving cycles, synthesized on the basis of statistical data on the movement of trucks across the territory of the Russian Federation. A synthesized driving cycle and a simulation model of truck movement, designed to determine the loads on the electromechanical transmission when moving along this cycle, are considered. Based on the results of simulation modeling of the movement of a truck with a different number of gears in a mechatronic transmission, conclusions about the influence of multi-speed transmissions on the energy efficiency of electric truck vehicle were drawn. Conclusions have been formulated about the required number of gears for mechatronic transmissions of trucks moving on the roads of the Russian Federation.

Electromechanical transmission of an all-wheel drive vehicle with a central traction electric motor

Modern approaches to the construction of a kinematic scheme of an electromechanical transmission are considered. It is shown that for all-wheel drive transport and transport-technological mobile platforms, it is advisable to use a central traction electric motor operating with a two-mode reduction gear connected in series and a transmission based on controlled inter-axle and inter-wheel power distribution mechanisms. It is shown that such a scheme makes it possible to improve the operating conditions of the traction motor, reduce its installed power, dimensions and weight. At the same time, it remains possible to fully control the traction force on the drive wheels, use power recovery, and work in the mode of dynamic stabilization of the motion trajectory. The structure of the electromechanical transmission based on the described principles is proposed. The principles of operation of controlled interaxle and interwheel power distribution mechanisms based on gear differentials are considered. Examples of simplified kinematic schemes of promising mechanisms are given and principles of their control are proposed. The principles of determination of external parameters and synthesis of kinematic schemes of interaxle and interwheel differentials with friction control are considered.